Search Results (943)

Multilevel active bridge converters are potential candidates for many modern high-power DC applications due to their ability to integrate multiple sources while minimizing weight and volume. Therefore, this paper deals with an analytical, simulation-based, and experimentally verified investigation of their circulating current behavior, power factor performance, and power loss characteristics. A high-frequency link analysis framework is developed to characterize voltage, current, and power transfer waveforms, providing insight into reactive power generation and its impact on overall efficiency. By introducing a modulation-based control approach, the proposed converters significantly reduce circulating currents and enhance the power factor, particularly under varying phase-shift conditions. Compared to quadruple active bridge topologies, the discussed multilevel architectures offer reduced transformer complexity and improved power quality, making them suitable for demanding applications such as electric vehicles and aerospace systems. Full article

Fibromyalgia (FM) is a complex chronic syndrome characterized by widespread pain, fatigue, and gastrointestinal complaints. Clinical observations and preliminary metabolomic data suggest a possible link between symptom severity and intestinal dysbiosis, including fungal overgrowth. This study investigates whether a carb-free oloproteic diet can beneficially modulate the gut microbiota in FM patients. Thirty-four female patients with diagnosed FM were enrolled in a controlled, parallel-arm nutritional intervention. Group FM1 (n = 22) followed a 45-day carb-free oloproteic diet followed by a 45-day low-glycemic (LOGI) diet. Group FM2 (n = 12) received a continuous LOGI diet for 90 days. They were collected at baseline (T0), after 45 days (T45), and at 90 days (T90). Microbial profiles were analyzed by 16S and 18S rRNA gene sequencing to assess bacterial and fungal composition. In FM1, the oloproteic phase led to a marked reduction in fungal abundance (Ascomycota) and an increase in butyrate-producing bacteria such as Faecalibacterium and Roseburia. These changes were partially reversed after the LOGI phase. In FM2, no significant microbiota shifts were observed. Clinical improvements paralleled microbiota modulation only in FM1. The carb-free oloproteic diet may support gut microbial rebalancing in FM, particularly through transient suppression of fungal overgrowth. These findings support further investigation into nutritional strategies targeting dysbiosis in FM management. Full article

Extracellular matrix (ECM) bioscaffolds have demonstrated therapeutic potential across a variety of clinical and preclinical applications for tissue repair and regeneration. In parallel, these scaffolds and their components have shown the capacity to modulate the immune response. Unlike synthetic implants, which are often associated with chronic inflammation or fibrotic encapsulation, ECM bioscaffolds interact dynamically with host cells, promoting constructive tissue remodeling. This effect is largely attributed to the preservation of structural and biochemical cues—such as degradation products and matrix-bound nanovesicles (MBV). These cues influence immune cell behavior and support the transition from inflammation to resolution and functional tissue regeneration. However, the immunomodulatory properties of ECM bioscaffolds are dependent on the source tissue and, critically, on the methods used for decellularization. Inadequate removal of cellular components or the presence of residual chemicals can shift the host response towards a pro-inflammatory, non-constructive phenotype, ultimately compromising therapeutic outcomes. This review synthesizes current basic concepts on the innate immune response to ECM bioscaffolds, with particular attention to the inflammatory, proliferative, and remodeling phases following implantation. We explore how specific ECM features shape these responses and distinguish between pro-remodeling and pro-inflammatory outcomes. Additionally, we examine the impact of manufacturing practices and quality control on the preservation of ECM bioactivity. These insights challenge the conventional classification of ECM bioscaffolds as medical devices and support their recognition as biologically active materials with distinct immunoregulatory potential. A deeper understanding of these properties is critical for optimizing clinical applications and guiding the development of updated regulatory frameworks in regenerative medicine. Full article

The rapid expansion of broadband wireless communication systems, including 5G, satellite networks, and next-generation IoT platforms, has created a strong demand for antenna architectures capable of real-time beam control, compact integration, and broad frequency coverage. Traditional reflectarrays, while effective for narrowband applications, often face inherent limitations such as fixed beam direction, high insertion loss, and complex phase-shifting networks, making them less viable for modern adaptive and reconfigurable systems. Addressing these challenges, this work presents a novel wideband planar metasurface that operates as a polarization rotation reflective metasurface (PRRM), combining 90° polarization conversion with 1-bit reconfigurable phase modulation. The metasurface employs a mirror-symmetric unit cell structure, incorporating a cross-shaped patch with fan-shaped stub loading and integrated PIN diodes, connected through vertical interconnect accesses (VIAs). This design enables stable binary phase control with minimal loss across a significantly wide frequency range. Full-wave electromagnetic simulations confirm that the proposed unit cell maintains consistent cross-polarized reflection performance and phase switching from 3.83 GHz to 15.06 GHz, achieving a remarkable fractional bandwidth of 118.89%. To verify its applicability, the full-wave simulation analysis of a 16 × 16 array was conducted, demonstrating dynamic two-dimensional beam steering up to ±60° and maintaining a 3 dB gain bandwidth of 55.3%. These results establish the metasurface’s suitability for advanced beamforming, making it a strong candidate for compact, electronically reconfigurable antennas in high-speed wireless communication, radar imaging, and sensing systems. Full article

In order to enhance the performance of 112 Gb/s polarization-multiplexed quadrature phase-shift keying (PM-QPSK) coherent optical receivers, a novel digital signal processing (DSP) framework is presented in this study. The suggested method combines cutting-edge signal processing techniques to address important constraints in long-distance, high data rate coherent systems. The framework uses overlap frequency domain equalization (OFDE) for chromatic dispersion (CD) compensation, which offers a cheaper computational cost and higher dispersion control precision than traditional time-domain equalization. An adaptive carrier phase recovery (CPR) technique based on mean-squared differential phase (MSDP) estimation is incorporated to manage phase noise induced by cross-phase modulation (XPM), providing dependable correction under a variety of operating situations. When combined, these techniques significantly increase Q factor performance, and optimum systems can handle transmission distances of up to 2400 km. The suggested DSP approach improves phase stability and dispersion tolerance even in the presence of nonlinear impairments, making it a viable and effective choice for contemporary coherent optical networks. The framework’s competitiveness was evaluated by comparing it against the most recent, cutting-edge DSP methods that were released after 2021. These included CPR systems that were based on kernels, transformers, and machine learning. The findings show that although AI-driven approaches had the highest absolute Q factors, they also required a large amount of computing power. On the other hand, the suggested OFDE in conjunction with adaptive CPR achieved Q factors of up to 11.7 dB over extended distances with a significantly reduced DSP effort, striking a good balance between performance and complexity. Its appropriateness for scalable, long-haul 112 Gb/s PM-QPSK systems is confirmed by a complexity versus performance trade-off analysis, providing a workable and efficient substitute for more resource-intensive alternatives. Full article

In order to solve the problem that it is difficult to take into account the performance constraints between the core functions of insulation, current flow and arc extinguishing of high-voltage vacuum circuit breakers at the same time, this paper proposes a flexible control strategy for the motor operating mechanism of high-voltage vacuum circuit breakers. The relationship between the rotation angle of the motor and the linear displacement of the moving contact of the circuit breaker is analyzed, and the ideal dynamic curve is planned. The motor drive control device is designed, and the phase-shifted full-bridge circuit is used as the boost converter. The voltage and current double closed-loop sliding mode control strategy is used to simulate and verify the realization of multi-stage and stable boost. The experimental platform is built and the experiment is carried out. The results show that under the voltage conditions of 180 V and 150 V, the control range of closing speed and opening speed is increased by 31.7% and 25.9% respectively, and the speed tracking error is reduced by 51.2%. It is verified that the flexible control strategy can meet the ideal action curve of the operating mechanism, realize the precise control of the opening and closing process and expand the control range. The research provides a theoretical basis for the flexible control strategy of the high-voltage vacuum circuit breaker operating mechanism, and provides new ideas for the intelligent operation technology of power transmission and transformation projects. Full article

Background/Objectives: Recent shifts in dietary patterns have led to reduced fiber consumption, corresponding with increasing rates of obesity and metabolic disorders. Barley-based cereals with high fiber content, particularly β-glucan, may provide superior metabolic and satiety benefits compared to corn-based alternatives. This study investigated whether barley-based cereals provide superior metabolic and satiety benefits compared to corn-based alternatives in overweight Korean adults. Methods: After selecting the most optimal cereal in the phase 1 study (acute postprandial research), a 6-week randomized controlled trial (RCT) was conducted in phase 2. In the phase 2 trial, overweight adults (n = 30; mean age of 43 ± 10.89 years; 36.7% female) were randomly assigned to consume either barley (n = 15) or corn cereal (n = 15) daily for 6 weeks. Participants consumed approximately 50 g of available carbohydrates (either barley or corn cereal) in 190 mL milk. Outcome measures included anthropometric parameters, fasting blood glucose, homeostasis model assessment of insulin resistance (HOMA-IR), postprandial glucose, subjective satiety, and gut health. Results: After 6 weeks, between-group comparisons revealed significant differences favoring the barley group in body weight (barley: −0.33 kg vs. corn: +0.85 kg; difference: −1.18 kg, p = 0.027), BMI (barley: −0.14 kg/m² vs. corn: +0.03 kg/m²; difference: −0.17 kg/m², p = 0.014), and glycated albumin (barley: −0.78% vs. corn: +0.09%; difference: −0.87%, p = 0.032). Within-group analyses showed that the barley group exhibited significant reductions in percent body fat (−1.03%, p = 0.004), waist circumference (−3.64 cm, p = 0.003), waist-to-hip ratio (−0.02, p = 0.012), glycated albumin (−0.78%, p = 0.029), and LDL cholesterol (−10.57 mg/dL, p = 0.033). Conversely, the corn group showed significant increases in body weight (+0.85 kg, p = 0.026) and percent body fat (+0.84%, p = 0.020), with a significant decrease in HDL cholesterol (−2.84 mg/dL, p = 0.020). Conclusions: Barley-based cereals offer significant metabolic and satiety benefits for overweight adults compared to corn-based alternatives. These findings suggest that barley-based cereals may be an effective dietary intervention for managing obesity and metabolic disorders. Full article

Terahertz (THz) communication is a key technology for sixth-generation (6G) networks, offering ultra-high data rates, low latency, and massive connectivity. However, the THz band faces significant propagation challenges, including high path loss, molecular absorption, and susceptibility to blockage. Reconfigurable intelligent surfaces (RISs) have emerged as an effective solution to overcome these limitations by reconfiguring the wireless environment through passive beam steering. In this work, we propose a novel framework, namely the optimized deep reinforcement learning transformer (ODRL-Transformer), to maximize the sum rate in RIS-assisted THz systems. The framework integrates a Transformer encoder for extracting temporal and contextual features from sequential channel observations, a DRL agent for adaptive beamforming and phase shift control, and a hybrid biogeography-based optimization (HBBO) algorithm for tuning the hyperparameters of both modules. This design enables efficient long-term decisionmaking and improved convergence. Extensive simulations of dynamic THz channel models demonstrate that ODRL-Transformer outperforms other optimization baselines in terms of the sum rate, convergence speed, stability, and generalization. The proposed model achieved an error rate of 0.03, strong robustness, and fast convergence, highlighting its potential for intelligent resource allocation in next-generation RIS-assisted THz networks. Full article

This paper focuses on the Input-Independent Output-Series (IIOS) DC converters within fully DC aggregation systems, which enable independent submodule control and high voltage gain. DC aggregation systems experience output voltage imbalance among submodules due to offshore wind power fluctuations. The proposed isolated DC/DC converter topology incorporates power-balancing capacitors, leveraging intrinsic characteristics to achieve self-power balancing within the system. In addition, this paper proposes an innovative PFMT-PSMN hybrid control strategy that is well-suited for the proposed topology. Firstly, this study performs a time-domain analysis of the intrinsically power-balanced DC series-connected aggregation topology and elucidates the corresponding power-balancing principle. Secondly, based on soft-switching boundary conditions, a hybrid control strategy, PFMT-PSMN, adjusts phase-shift duty cycles to maintain soft-switching conditions while minimizing the system operating frequency. Finally, MATLAB/Simulink simulations validate the power-balancing capability of the intrinsically balanced DC series-connected aggregation system and the effectiveness of the proposed PFMT-PSMN control strategy. Full article

The impact of invasive alien species (IAS) is one of the direct factors causing global biodiversity decline and economic losses, and predicting the potential invasion risks of invasive species is crucial for developing prevention and control strategies. In recent years, an increasing number of studies have shown that invasive species undergo rapid shifts in climate niche in invaded areas. Accurately quantifying the dynamic shifts in the climate niche of invasive species in invaded areas is crucial for developing a more accurate framework for early warning of invasive species risks. Pomacea canaliculata is a freshwater snail found in South America and has become one of the most aggressive aquatic species in the world. Since its introduction to China in 1981, it has rapidly spread and caused multiple serious damages to agriculture, ecology, and public health. Therefore, based on multi-source distribution data of P. canaliculata, this study calculated the climate niche overlap by Schoener’ s D, quantified the niche shifts between the P. canaliculata in native and invaded areas (China) via the COUE scheme (a unified terminology representing niche centroid shift, overlap, unfilling, and expansion), and analyzed their changes on a time scale. The results revealed that there have been significant climate niche shifts (Schoener’s D < 0.2, niche similarity tests p > 0.01, niche equivalence tests p < 0.01) between the native and invaded areas (China) of P. canaliculata, which does not support the climate niche conservation hypothesis. The minimum temperature of the coldest month (Bio 6) and precipitation seasonality (Bio 15) were the key climate variables driving the climatic niche shift, and P. canaliculata can survive in colder and more arid regions than their native counterparts. The changes in the niche shifts in P. canaliculata on a time scale show significant temporal heterogeneity, and its invasion behavior in China presents a discontinuous and phased expansion pattern, with strong adaptability to new environments. The results are of great significance for the future development of more accurate ecological niche model (ENM), the formulation of more targeted prevention and control strategies, and the study of adaptive evolution mechanisms of invasive species. Full article

This paper introduces the overall design plan, development timeline, and preliminary progress of the Autonomous Pit Exploration System project. This project aims to develop an advanced multi-robot system for the efficient inspection of nuclear waste-storage tank pits. The project is structured into three phases: Phase 1 involves data collection and interface definition in collaboration with Hanford Site experts and university partners, focusing on tank riser geometry and hardware solutions. Phase 2 includes the selection of sensors and robot components, detailed mechanical design, and prototyping. Phase 3 integrates all components into a cohesive system managed by a master control package which also incorporates digital twin and surrogate models, and culminates in comprehensive testing and validation at a simulated tank pit at the Idaho National Laboratory. Additionally, the system’s communication design ensures coordinated operation through shared data, power, and control signals. For transportation and deployment, an electric vehicle (EV) is chosen to support the system for a full 10 h shift with better regulatory compliance for field deployment. A telescopic arm design is selected for its simple configuration and superior reach capability and controllability. Preliminary testing utilizes an educational robot to demonstrate the feasibility of splitting computational tasks between edge and cloud computers. Successful simultaneous localization and mapping (SLAM) tasks validate our distributed computing approach. More design considerations are also discussed, including radiation hardness assurance, SLAM performance, software transferability, and digital twinning strategies. Full article

Phase-shifting transformers (PST) are widely used to control power flows. However, conventional designs can vary only the phase angle, leaving the voltage magnitude unaffected or requiring structurally complex devices. This study proposes a compact PST topology that realizes simultaneous, decoupled control of both voltage magnitude and phase angle through two coordinated sets of windings. Closed-form equations are derived to link the phase-shifting and voltage regulation windings turn ratios to any target magnitude ratio and phase-shift angle, providing a unified design framework that guarantees the full practical operating range. Steady-state tests verify that the device can change the phase or adjust the magnitude independently without cross-coupling. Dynamic tests demonstrate that, when a tap command is issued, the line currents and active power converge to new set-points within a few fundamental periods and with minimal oscillation. Furthermore, the PST’s application to loop closing operations in 220 kV networks is investigated, where simulation results show it can suppress loop closing currents by over 90% under adverse voltage mismatch conditions. These results confirm that the proposed PST offers a fast, economical alternative to Flexible AC Transmission Systems (FACTS) equipment for real-time power flow balancing, renewable integration and inter-area exchange in modern transmission networks. Full article

Background: The World Health Organization (WHO) defines health promotion as the process of enabling individuals to gain control over and improve their health. This shifts the focus from lifestyle choices to broader social determinants of health, requiring involvement from healthcare, authorities, industry, civil society, and the media. Civil society engagement in health initiatives offers benefits such as empowerment, service delivery, flexibility, policy participation, and credibility. However, identifying specific health promotion actions for civil society organizations (CSOs) is challenging. The lack of assessment tools for CSOs hinders evaluation and improvement. Objective: To develop a tool, ‘PromoACTIVA-SC’, to assess CSOs’ health promotion practice by identifying essential actions that constitute the health promotion process. Methods: ‘PromoACTIVA-SC’ was developed through documentary analysis and validated by experts. CSOs’ members participated in cognitive interviews for comprehensibility, and the tool was pilot tested for administration and Likert scale evaluation. Results: The final questionnaire, consisting of 8 phases and 40 items, demonstrated good content validity. Its use can help to map CSOs’ practices and identify areas needing improvement. CSOs can use it for self-assessment and in collaborative health promotion and disease prevention efforts. Conclusions: ‘PromoACTIVA-SC’ is the first tool designed to assess civil society’s role in the health promotion process. Its future use will reveal the extent to which civil society organizations actively participate in health promotion. It can also be used to promote CSOs’ involvement in health policy and administration, enhancing public health outcomes through collaborative, cross-sectoral efforts. Full article

Polymer viscoelasticity is crucial for mechanical performance, but conventional low-frequency methods struggle to isolate viscous loss—a key viscosity indicator. This study introduces a high-frequency ultrasonic method to differentiate the polymer viscous dissipation index by analyzing acoustic phase shifts. We employ ultrasonic phase-shift thermometry to measure localized temperature increases resulting from minute variations in sound velocity during controlled heating. This allows for the quantification of viscous loss, which is then used to distinguish between different polymer formulations. Experimental and simulation results on a series of polyurethane specimens with varying Shore hardness levels demonstrate that decawatt-range (10–20 W) ultrasonic irradiation enables sensitive and precise differentiation. Notably, the Shore A70 polyurethane sample exhibited a significantly higher viscous dissipation index, evidenced by the largest temperature rise (27.5 °C) and the highest proportion of viscous heating to total power dissipation (93.1%) under 17 W acoustic irradiation. While this study focuses on commercially available polymers, the method can be extended to evaluate key performance parameters, such as tensile modulus and glass transition temperature, in polymers fabricated under various processing conditions, thereby offering a powerful tool for material quality assessment. Full article

Chronic liver disease is a significant global cause of morbidity and mortality. While early-stage liver cirrhosis is often asymptomatic, it can progress to a decompensated phase known as end-stage liver disease (ESLD), resulting in a high symptom burden, diminished quality of life, and frequent hospitalizations. Palliative care is a form of specialized care aimed at addressing the needs of patients; however, it remains underutilized in ESLD patients. Globally, the integration of palliative care into ESLD is impeded by several barriers. Certain factors—such as advanced age, the presence of hepatocellular carcinoma (HCC), and transplant listing status—have been associated with higher rates of palliative care referral. This review provides a comprehensive analysis of the current literature, emphasizing the benefits of palliative care interventions in ESLD, including improved symptom control and enhanced quality of life. It also underscores the impact on caregivers and healthcare systems, notably in reducing hospital readmissions. We advocate for a paradigm shift toward proactive, patient-centered models that integrate symptom management, advance care planning, and psychosocial support alongside disease-specific treatments for patients with ESLD. Full article